BACKGROUND: Elemental diet is considered an effective primary treatment for active Crohn's disease, but it is usually given by a feeding tube.

METHODS: Twenty-two patients (12 males, median age 30 years, range 18-60) with moderately active Crohn's disease were enrolled in a randomized study in which the efficacy of an elemental diet administered orally was compared to high-dose corticosteroids in achieving clinical and laboratory remission. Ten patients were treated by oral elemental diet (Peptamen, Clintec, USA) and 10 received corticosteroids. Both treatment regimens lasted 2 weeks. The two groups did not differ with respect to age, sex, body weight, location of disease, treatment or disease activity prior to the study. In all patients studied, simple Crohn's disease activity index, nutritional status (expressed as body mass index), percentage of ideal body weight, fat mass, fat free mass, erythrocyte sedimentation rate, interleukin-6, intestinal permeability (expressed as permeability index), prealbumin, retinol binding protein and multiskin test were evaluated before and after treatment.

RESULTS: After 2 weeks of treatment, there were significant improvements in simple Crohn's disease activity index, erythrocyte sedimentation rate, permeability index, body mass index, prealbumin, retinol binding protein and multiskin test in the elemental diet group. There were significant improvements in simple Crohn's disease activity index and fat free mass in the corticosteroid group.

CONCLUSIONS: These data suggest that, in the short term, an oral elemental diet is at least as effective as steroids in inducing remission of mild-moderately active Crohn's disease, but it may be more effective in improving the nutritional status of these patients, probably through a more rapid restoration of normal intestinal permeability.

Elemental diets (EDs) are effective in treating Crohn's disease. We hypothesize that low dietary fat and amino acids used as the sole nitrogen source are the major contributors for the success of EDs. We examined the influences of the addition of dietary fat and protein to an ED using an indomethacin-induced inflammation model in rat small intestine. In the ED-fed rats, the intestinal damage score was decreased compared with that in the standard chow group with decreasing intestinal permeability. By supplementing an ED with soybean oil (SO), intestinal permeability was increased to a level similar to that of the standard chow group. For this group, the intestinal damage score also increased compared with that of the ED group but did not reach the levels observed in the standard chow group. The addition of dietary proteins (using heat-denatured pancreatin) resulted in intestinal damage scores that were significantly higher than those of the ED+SO-fed group. The dietary protein increased the intestinal damage score. These results suggest that EDs control inflammation by decreasing intestinal permeability and the elimination of dietary proteins.

The beneficial effects of caloric restriction in increasing longevity and forestalling age-related diseases are well known. Dietary restriction of methionine also renders similar benefits. We recently showed in a renal epithelial cell culture system that reduction of culture medium methionine by 80% resulted in altered tight junctional (TJ) claudin composition and also improved epithelial barrier function (51). In the current study, we examined the effect of dietary restriction of methionine on TJ barrier function in rat gastrointestinal tissue in order to see if this phenomenon also holds true in a tissue model and for a different epithelial cell type. After 28 days on methionine-restricted (MR) diet, rats showed small but significant reductions in the plasma and (intracellular) colonocyte levels of methionine. Colon mucosal sheets from rats on MR diet showed increased transepithelial electrical resistance with concomitant decrease in paracellular diffusion of (14)C-D-mannitol suggesting improved barrier function relative to rats on control diet. This improved barrier function could not be explained by changes in colon crypt length or frequency. Neither was the colonocyte mitotic index nor the apoptotic frequency altered significantly. However, TJ composition/structure was being altered by the MR diet. RT-PCR and Western blot analysis showed an increase in the abundance of claudin-3 and an apparent change in the post-translational modification of occludin, data reinforcing a paracellular barrier alteration. Overall, our data suggest that reduction in dietary intake of methionine results in improved epithelial barrier function by inducing altered TJ protein composition.

OBJECTIVE:To probe into effect of electroacupuncture on intestinal permeability in the patient with acute pancreatitis and the mechanism.

METHODS:Sixty-eight cases of acute pancreatitis were randomly divided into a treatment group and a control group. The control group and the treatment group were treated with anti-infection, inhibiting secretion of pancreas, improving microcirculation and protective agent of gastric mucosa, with electroacupuncture at Zusanli (ST 36), Shangjuxu (ST 37), Gongsun (SP 4), Taichong (LR 3) and Xuanzhong (GB 39) added, twice daily for 3 days, in the treatment group. Their clinical therapeutic effects and changes of endothelin (ET), nitric oxide (NO), tumor necrosis factor (TNF-alpha) and lactulose/mannose ratio (L/M) before and after treatment were compared.

RESULTS:The total effective rate of 86.7% in the treatment group was better than 76.3% in the control group (P<0.05). After treatment, ET, NO, TNF-alpha contents and L/M all were higher than those before treatment, with those in the treatment group being significantly lower than those in the control group (P<0.05).

CONCLUSION:Electroacupuncture can significantly decrease permeability of intestinal mucosa in the patient with acute pancreatitis, reduce accumulation of endogenous inflammatory mediators (ET, TNF-alpha) and vascular active substance (NO) in intestinal mucosa, so as to alleviate necrosis of intestinal epithelial cells and protect the barrier of gastro-intestinal mucosa.

Enteral intake of non-metabolic monosacharide and disaccharide, followed by measurement of the urinary excretion ratio of the two, is a method used to investigate intestinal permeability. L/R ratio (lactulose/1-rhamnose urinary excretion ratio) is considered an indicator of permeability of the small intestine. An increased L/R ratio is caused by mucosal disorders of the small intestine. The L/R ratio in all patients (n = 92) with Crohn's disease was 0.079 +/- 0.081 (mean +/- S.D.), which was significantly higher than the value in normal controls (0.027 +/- 0.009, n = 20, p<0.05). In 39 patients with Crohn's disease, we assessed intestinal permeability before after treatment with an elemental diet, and during remission. The L/R ratio was 0.120 +/- 0.092, before treatment and 0.065 +/- 0.097 after treatment (p<0.05), showing increased intestinal permeability before elemental dietary treatment. During remission, the L/R ratio was 0.035 +/- 0.028; this did not differ significantly from the value obtained after treatment. We conclude that intestinal permeability is useful for investigating disease activity in patients with Crohn's disease.

This study examines whether treatment of acute Crohn's disease with an elemental diet improves intestinal integrity and inflammation as assessed by a 51Cr-labeled ethylenediaminetetraacetatic acid (EDTA) permeability test and the fecal excretion of 111In-labeled autologous leukocytes, respectively. Thirty-four patients with active Crohn's disease completed a 4-week treatment course with an elemental diet. Active disease was characterized by increased intestinal permeability [24-hour urine excretion of orally administered 51Cr-EDTA, 6.4% +/- 0.6% (mean +/- SE); normal, less than 3.0%] and by high fecal excretion of 111In-labeled leukocytes (14.2% +/- 1.1%; normal, less than 1.0%). Twenty-seven (80%) went into clinical remission, usually within a week of starting treatment. After 4 weeks of treatment, there was a significant decrease in both the urine excretion of 51Cr-EDTA (to 3.4% +/- 0.5%; P less than 0.01) and the fecal excretion of 111In (to 5.7% +/- 1.0%; P less than 0.001), indicating that such treatment is not just symptomatic. A framework for the mechanism by which elemental diet works, centering around the importance of the integrity of the intestinal barrier function, is proposed, and also appears to provide a logical explanation for some relapses of the disease.